Pros

Cons

Bottom Line

Versatile, comfortable, and highly accurate, the Polar H10 is one of the best heart rate monitors money can buy.

15 Aug 2017

Polar has set a pretty high bar in the heart rate monitor department, so it's no surprise that it isn't trying to reinvent the wheel with its latest chest strap, the H10 Heart Rate Sensor ($89.95). It's more of a refinement on the popular H7, which is considered a gold standard by many (and our go-to device for comparison testing). The H10 maintains that accuracy, while improving battery life and adding onboard memory, making it more convenient for athletes who hate working out with their phone in tow. It falls just shy of earning our Editors' Choice, however, as the outstanding Wahoo Fitness Tickr X offers a wider range of compatible devices and apps, as well as physical feedback features for $10 less. Even so, the H10 is an excellent choice that deserves a spot at the top of your short list.

New and Improved

The H10 strongly resembles the Polar H7 from a design perspective, albeit with some key improvements. The snap-on sensor is smaller and thinner; the strap has a new buckle that's easier to adjust and put on; and the inside features electrodes and silicone dots to prevent slippage (more on these in the next section). But where the H7 is available in a few different color choices, the H7 only comes in black. That's not a major drawback, as you're probably not going to be spending much time showing it off (unless you exercise shirtless).

Most of the other improvements aren't visible. The H10 can receive software updates wirelessly, for one. It also has double the battery life of the H7, 400 hours, which should translate to months of usage. And since it uses a regular coin cell battery, you never have to charge it. I've been exercising regularly with the H10 for about four months, and it still registers as having a full battery. Another bonus: the back of the sensor has an updated design that makes replacing the battery easier. Like the H7, you can use the H10 while swimming, which is something you can't do with the Tickr X.

But the biggest update is that the H10 has built-in memory, so it can store one training session before syncing. That's not much compared with a traditional fitness tracker, but it adds some flexibility. Whereas the H7 needs to be constantly connected to your phone in order to transmit data, with the H10 you only need your phone to start recording, but then you can leave it at home, in the locker room, or anywhere else that's out of range, and it will sync later.

The H10 doesn't have a screen, so unless your phone is available, you won't get any real-time feedback unless you use it with compatible gym equipment via Polar's proprietary GymLink connection.

Comfortably Invisible

The H10 is comfortable enough that you can wear it all day long. It comes in two sizes: XS-S (20-26 inches) and M-XXL (26-36 inches). I wore the strap during indoor and outdoor runs, as well as at the office. I never experienced chafing, and within a few seconds, it was easy to forget I was even wearing it. It did ride up under my sports bra on occasion, but the sensor's slim profile never caused enough discomfort to require readjustment. And unless you're wearing skin-tight clothes, no one will be able to tell you're wearing it.

That said, it's not quite as simple as buckling the H10 into place. First, you have to dampen the electrodes with some water to ensure you get a reading. After that, you can snap the sensor into place on the front. After any strenuous activity you'll want to briefly clean the strap and detach the sensor. According to Polar, this helps preserve battery life, as the electrodes may continue to record data mistakenly. You can also throw the strap itself in the washing machine.

The App Experience

You can use the H10 with third-party fitness apps like Cardio Mapper, Endomondo, iSmooth Run, and Runtastic, but it's optimized to work with Polar's own Beat and Flow apps. Both are free, though you'll have to pay if you want to unlock all of Beat's features.

Beat is essentially for recording training sessions. It's also the app you use to pair the H10 over Bluetooth. In the free version, you can see your heart rate and view simplified statistics such as duration, average heart rate, and calories burned. You can select from an extensive range of activities to track that run the gamut from running, to Latin dancing, to wakeboarding, but otherwise it's really the bare minimum.

If you want more insight into training intensity, or how you've progressed, you'll have to pay for it. There are four upgrades: Benefit Target, Energy Pointer, Fitness Test, and Running Index. Benefit Target and Energy Pointer give you real-time guidance for your workout, while Running Index lets you track your run performance over time. Fitness Test lets you measure your VO2 Max score in about five minutes as you lie down and relax. Individually, these features cost $2.99, but you can get them all in a bundle for $7.99. It's not expensive, but similar features don't cost extra with apps from Fitbit, Garmin, and Jabra, for instance.

The Polar Flow app is a more holistic look at your activity, and functions more like your typical fitness tracker app. You can track sleep, view your daily activity level, and see how many steps you've taken in a day. However, the H10 doesn't track these metrics, and unless you plan on using it with another Polar tracker, like the M430, you don't really need it. But if you do pair it with a Polar tracker, your recorded sessions sync automatically and seamlessly.

Accuracy

Wrist-based trackers, like the Fitbit Charge 2, typically use optical LEDs that measure blood flow based on light reflecting off your skin. They're pretty accurate, especially in recent years, but readings can be off if you don't wear them correctly.

You're much less likely to get skewed readings with a chest strap. For starters, they're unlikely to slip and are placed much closer to the heart. Also, they use electrical signals, rather than light, to measure your heart beat. And among chest straps, Polar has a stellar reputation for accuracy. In fact, we used the H7 as a benchmark in testing the accuracy of other wearables with heart rate monitoring.

I conducted three one-minute pulse tests to check the H10's accuracy. To do this, I set a timer and counted my pulse while simultaneously wearing the H10. Each time, the reading was accurate within two to three beats per minute. For context, most trackers I've tested tend to vary closer to five to ten beats. If you want to seriously incorporate heart rate zone training into your routine, it's hard to outdo the H10 for reliable accuracy.

I did notice, however, that there is a slight lag when using the GymLink feature on intense workouts. As my heart rate climbed above 170bpm, the treadmill I was on would regularly report it as 140 to 150bpm. You often see a similar lag with wrist-based wearables. For the most accurate results, you're better off sticking with real-time monitoring via the app or viewing your data later.

What HRM Is Right for You?

If your current H7 chest strap is showing some wear and tear, you might want to think about upgrading to the H10. The extended battery life and built-in memory make it a solid investment, especially if you have or are thinking of getting a Polar fitness tracker.

That said, if you're buying your first heart rate monitor and you aren't a Polar user, the Wahoo Fitness Tickr X costs less and offers some features you might prefer. It includes vibration and LED feedback, which can be customized to let you control your music or inform you when you reached a milestone in your workout. And in addition to being highly accurate, you can use it with a wider range of devices and apps, including Strava and RunKeeper. For these reasons the Tickr X remains our Editors' Choice, but depending on your needs the H10 could be the right choice for you.

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About the Author

Victoria Song is an analyst on the Hardware team at PCMag. Since graduating from Temple University’s Japan Campus in 2010, she's been found reporting and editing in every corner of the newsroom at The ACCJ Journal, The Japan News, and New York bureau of The Yomiuri Shimbun. In her spare time, she bankrupts herself going to theater, buying expansions to board games, and cleaning out the stacks at The Strand. Someday, she hopes Liverpool FC will win the league, but she isn’t holding her breath.